The thermoluminescence characteristics and selected frequency luminescence characteristics of an orthoclase were studied using RGD-3B thermoluminescence dosimeter and BG2003 luminescence spectrograph. The result indicates that the orthoclase has three thermoluminescence peaks and the temperatures of these peaks are 148, 197 and 310 ℃ respectively. The 197 and 310 ℃ thermoluminescence peaks appear when it has been irradiated. The temperature of peak value deceases with the decease in warming rates. The luminescence signal is obvious at 290, 300, 310, 340, 400 and 480 nm wavelength with heat excitation. The luminescence signal is obvious at 280, 290, 300, 310, 320, 400, 460 and 480 nm wavelength with 532nm light excitation. The certain linear relation exists between the photon counts from 400 nm and irradiation doses. It can also be used as a dosimeter. It has application potential in luminescence dating.